Instructions
Download the PS3SX emulator for the Sony PS3 from a computer.
Connect a USB flash drive to the computer on which the PS3SX file was downloaded. Click "Open folder to view files" in the AutoPlay window that appears.
Click "New Folder" and type "psxrom" as the folder name. Save all of your PS1 backup games in this folder.
Right-click the PS3SX file and select "Copy" from the menu. Right-click the USB drive from the list of drives on your computer.
Select "Paste" from the menu that appears. Pull the USB drive out of the computer's USB port and then insert it into the PS3's USB port.
Select "Install Package Files" from the PS3's menu. A screen with all of the PKG files on the USB drive appears.
Select the "PS3SX" PKG file to install the PS1 emulator on the PS3. Press the "O" button to return to the PS3 menu.
Select the PS3SX icon on the PS3 menu to run the PS1 emulator on the PS3. A list of installed PS1 backup games appears. Select the PS1 backup game that you wish to play.